Total salivary fluoride concentrations of healthy adult subjects following toothbrushing with different formulations of fluoridated toothpastes with and without post-brushing water rinsing : a double blinded randomised controlled trial

Background: Caries prevalence has declined significantly since the introduction of fluoridated toothpastes. There have been a number of developments with regards to specific active fluoride ingredients but not enough evidence to support one over the other. Aim: To compare the salivary fluoride concentrations of different fluoride formulations in the form of toothpaste: fluoride-free (0 ppmF), sodium fluoride (1,450 ppmF), sodium monofluorophosphate (1,450 ppmF), sodium fluoride and monofluorophosphate combined (1,450 ppmF), stannous fluoride and sodium fluoride combined (1,450 ppmF) and amine fluoride (1,400 ppmF) with and without post-brushing water rinsing. Design: Study registered with ClilincalTrials.gov public database (NCT02740803). In vivo double-blinded randomised controlled trial measuring salivary fluoride concentrations following brushing with six toothpaste formulations. Power calculation was performed using PASS11.0 software and the total sample size of 120 was recruited in this study. Participants brushed with 1.0g of one of six different formulations of toothpastes either with or without water rinsing post-brushing. Participants were randomly assigned to groups using an online random team generator. Saliva was collected at six different times (baseline and at 1, 15, 30, 60 and 90 minute(s) post-brushing). Samples were analysed using a fluoride ion-specific sensitive electrode connected to an ion analyser. Codes were broken after data analysis. Data analysis was performed using IBM SPSS 23 software. Results: Demographic characteristics were not significant variables (p > 0.05). Time, toothpaste formulation and rinsing methods had significant effects (p < 0.05). In general, amine fluoride toothpaste resulted in significantly higher salivary fluoride concentrations at 90 minutes than control groups, in both rinsing and non-rinsing groups. Sodium monofuorophosphate toothpaste did not result in significant difference compared to control group at any time point, in both rinsing and non-rinsing groups. Conclusion: The results of this study supports the current recommendation of no rinsing post-brushing. It also supports the previous literature in that amine fluoride resulted in significantly higher fluoride concentrations.